Mixing device



13, 1940- R. w. sco'r'r MIXING DEVICE Filed Feb. 26, 1938 2 Sheets-Sheet. 1

v 5 W, m WW v/ @M m Patented Aug. 13, 1940 MIXING DEVICE Ray w. Scott,Detroit, Micln, assignor to Bendix Home Appliances, Inc., South Bend,but, a corporation of Delaware Application February 26, 1938, Serial No.192,692

g 4 Claims. This invention relates to mixing devices and moreparticularly to devices for-mixing hot and vide an extremely simple yetpositive and reliable device for maintaining a function of a mixture offluids constant. 7

Another object of the invention is to provide a mixing device for hotand cold fluids in which the relative proportions of the fluids arecontrolled by thermostatic means entirely housed within the mixingchamber. In one preferred form the thermostatic means is an elongatedbimetal strip extending substantially from the inlet to the outlet ofthe mixing chamber.

Another object of the invention is'to provide a mixing device having abimetal strip controlling admission of fluid to be mixed and includingnovel mounting means for the strip.

Another object is to provide a mixing device including a valvemembercontrolled by a bimetal strip in which the strip is so formed asnot to interfere with mixing of the fluids. Preferably the strip is cutout adjacent the valve member to permit free intermingling of fluidsadmitted past the valve,

Other objects, advantages and novel features of the invention will beapparent from the follow- Figure 4 is a center section of another modi-'fled mixing device employingbimetallicstrips protected against corrosionby a covering .of rubrated by web 28. The opening I8 communicates with apipe 22 leading to a source of cold-water or the like and the opening I8communicates with a pipe 24'leading to a source of hotiwater or thelike.

The opposite end of the tube It carries an out- (Cl. ass-.12)

let nipple 26 and a perforated plug 28 adjacent to the outlet nipple.

In order to control the relative amounts of hot and cold fluid admittedto the mixing chamber, a disk 38 provided with a centeraperture 32 5 isslidably mounted against the inner face of the plate I4 with theaperture in register with the openings I6 and I8. The disk is connectedto one end of a bi-metal thermostatic strip 34, the opposite end ofwhich is flxed to the plug 28 10 as by means of a rivet 36. As best seenin Figure 2, the strip 34 is secured to the disk 38 on opposite sides ofthe aperture 32 and has a cut-out portion 38 in register with theaperture to permit ready mingling of fluid on opposite sides of the i5strip. It will alsobe noted that the strip 34 serves as a strut tosupport the disk 38 against the plate I4..

The setting of the strip 34 is controlled by a pair of screws 48threaded through caps 42 which go extend through the tube I8 on oppositesides of the strip. If desired, covers 44may be secured to the ends ofthe caps 42 to cover the ends of the screws 48.

In operation the screws 48 are adjusted to ten- 25 sion the strip 34 toproduce any desired mixture temperature. If the temperature of mixedfluid in the mixing chamber I8 becomes too high,-the strip will deflectin a direction to restrict the opening I8 and to open further theopening I6. 30 This will admit an increased amount of cold water and asmaller amount .of hot water to bring the temperature back to thedesired value.

In the mixing device illustrated in Figure 3, parts corresponding toparts shown in Figures 5 1 and 2 are designated by the same referencenumerals increased by 100 and such parts will I notbe particularlydescribed hereafter.

This deviceis characterized by the use of a plurality of bimetallicthermostatic strips I34, e, g., three such strips, instead of a singleone, whereby 'thevalve disk I38 is better supported against the pressureof the water issuing from the openings H6 and H8 and whereby the poweravailable to shift the disk I38 is augmented. 'Inc 46 three strips aresecured in face to face relationship in spaced parallel slots in theplugor support I28 by means of a rivet I36.

In the illustrated device, I prefer to provide on the center strip I34spacing means in the form of a rivet 48 positioned in axial alignmentwith'the, adjusting screws I48 and projecting on each side of the centerstrip to engage the outer strips, .By this means adjustment or thescrews I48 istransmltted to all of the strips I34. v 4* In themodification of Figures 4 and 5 corresponding parts are designated bythe same reference numerals plus 200. This modification is characterizedby the use of a coating of rubber or resin or similar corrosionresisting material 48 applied by dipping or spraying or the like to thesurface of the strips 234 (two in number) and the plug 228 to form anunbroken sheath thereover. The strips are secured in slots in the plug228 by a rivet 236 in the same manner as the strips of the precedingmodifications and the plug 228 is held securely in place by beingclamped between a shoulder 56 formed in the tube are and the outletnipple 226 threaded into the end of the tube me.

In order to simultaneously adjust both strips and reduce the possibilityof abrasion of the coating 48, I provide a yoke 2G6 closely holding thetwo strips and engaged by the screws 2%.

While three embodiments of the invention have been shown and describedin detail, it will be understood that various changes might be madetherein and that the illustrated devices might be employed to controlmixture of substantially any desired fluids. It is accordingly notintended to limit the scope of the invention to the exact forms shownnor otherwise than by the terms of the appended claims.

What is claimed is:

l. A mixing device comprising an elongated tubular mixing chamber, aplate at one end of the mixing chamber formed with a pair of spacedopenings communicating with sources of hot and cold water respectively,a perforated plug in the other end of the mixing chamber, a bimetalstrip secured at one end to said plug and extending through the mixingchamber substantially to said plate, and an apertureddisc connected tothe other end of said strip and slidable across said plate, said striphaving a cut out portion therein opposite the aperture in the disc.

2. A mixing device comprising an elongated tubular mixing chamber, aplate at one end oi the mixing chamber formed with a pair of spacedopenings communicating with sources of hot and cold water respectively,a perforated plug in the other end of the mixing chamber, a bimetalstrip secured at one end to said plug and extending through the mixingchamber substantially'to said plate, and an apertured disc connected tothe other end of said strip and slidable across said plate, said stripserving as a strut to support the disk against the plate.

3. A mixing device comprising an elongated.

tubular mixing chamber, a plate at one end of the mixing chamber formedwith a pair of spaced openings communicating with sources of hot andcold water respectively, a perforated plug in the other end of themixing chamber, a bimetai strip secured at one end to said plug andextending through the mixing chamber substantially to said plate, and anapertured disc connected to the other end of said strip and slidableacross said plate, said strip having a cut-out portion therein oppositethe aperture in the disc, said mixing chammr having adjustably mountedin its opposite side walls members engaging opposite sldes of said stripnear said plug, and said strip serving as a strut to support the diskagainst the plate. 7

A mixing device comprising a mixing cham her, a plate forming one wallof the mixing chamber and having therein a pair of spaced cold liquidrespectively, an apertured disk s able over said plate, a support in themixing chamber, and a plurality of spaced bimetal strips secured at oneend to the support and at the other end to the disk to move the disk inresponse to variations in the temperature of fluid in the mixingchamber, said bimetal strips being arranged in parallel face tofacerelationship and acting as spaced struts to support the disc againstthe plate.

RAY W. SCOTS.

